| Title |
An Efficient Unified Method to Compute Voltage Collapse Point |
| Authors |
남해곤(Nam, Hae-Gon) ; 김동준(Kim, Dong-Jun) ; 송충기(Song, Chung-Gi) ; 문영환(Mun, Yeong-Hwan) ; 김태균(Kim, Tae-Gyun) ; 이효상(Lee, Hyo-Sang) |
| Keywords |
voltage collapse ; nose curve ; Point of Collapse method ; continuation power flow ; a pair of multiple load flow solutions ; Lagrange interpolation |
| Abstract |
The saddle node bifurcation (SNB) and the distance voltage instability are valuable information in power system planning and operation. This paper presents a new efficient, robust and unified strategy to compute the SNB by the combined use of the continuation power flow (CPF), Point of Collapse (PoC) method, and the method of a pair of multiple load flow solutions (PMLFS) with Lagrange interpolation utilizing only their advantages: the approximate nose curves and critical loading are determined fast by Lagrange-interpolating two stable and two unstable solutions obtained by using the robust CPF and PMLFS; the exact SNB is computed by the quadratically converging PoC method. The proposed method has been tested on Klos-Kerner 11-bus, New England 30-bus, IEEE 118-bus and KEPCO 791-bus systems. The method is found to be so efficient that computation time for determining the SNB of the KEPCO 791-bus system is 17.82 sec by a notebook PC with 300 MHz Pentium processor. |